PBDB Timescale

North American Mammal Subages/Zones

The interval definitions in this timescale are derived from the following sources:

M. O. Woodburne. 1987. A prospectus of the North American Mammal Ages. In: Woodburne, M. O. (ed.), Cenozoic Mammals of North America. University of California Press, Berkelery, CA 285-290 view
J. Alroy. 2000. New methods for quantifying macroevolutionary patterns and processes. Paleobiology 26(4):707-733 view
W. B. Harland, R. L. Armstrong, A. V. Cox, L. E. Craig, A. G. Smith and D. G. Smith. 1990. A Geologic Time Scale 1989. view
F. M. Gradstein, J. G. Ogg, and A. G. Smith. 2004. A Geologic Time Scale 2004 1-589 view
F. F. Steininger, W. A. Berggren, D. V. Kent, R. L. Bernor, S. Sen and J. Agusti. 1996. Circum-Mediterranean Neogene (Miocene and Pliocene) marine-continental chronologic correlations of European mammal units. The Evolution of Western Eurasian Neogene Mammal Faunas (eds. R. L. Bernor, V. Fahlbusch, and H.-W. Mittmann) view
K. M. Cohen, S.C. Finney, P.L. Gibbard and J.-X. Fan. 2023. The ICS International Chronostratigraphic Chart v2023/09. view
P. L. Gibbard, M. J. Head, and M. J. C. Walker. 2010. Formal ratification of the Quaternary System/Period and the Pleistocene Series/Epoch with a base at 2.58 Ma. Journal of Quaternary Science 25(2):96-102 view
A. D. Barnosky, M. Holmes, R. Kirchholtes, E. Lindsey, K.C. Maguire, A.W. Poust, M.A. Stegner, J. Sunseri, B. Swartz, J. Swift, N.A. Villavicencio and G. Wogan. 2014. Prelude to the Anthropocene: Two new North American Land Mammal Ages (NALMAs). The Anthropocene Review I(3):225-242 view

There are 13 timescales which overlap this one. show

Interval boundaries marked with * have been interpolated based on the differences between the ages for international timescale boundaries quoted in the source and the currently accepted ages for those boundaries.

Interval names marked with † are no longer in current use.

This timescale is used in the definition of 1028 collections

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International Chronostratigraphic Timescale			North American Mammal Subages/Zones			Cenozoic Subepochs	European Faunal Units	Obsolete Names for ICS Units			Cenozoic Subepochs of Southern Europe	North American Land Mammal Ages
Quaternary	Holocene	Meghalayan										Saintaugustinean	0
		Meghalayan										Santarosean	0.0004
		Northgrippian											0.0042
		Greenlandian											0.0082
	Pleistocene	Late Pleistocene	Sheridanian			Late Pleistocene					Tarantian		0.0117
		Late Pleistocene				Late Pleistocene					Tarantian	Rancholabrean	0.014
		Chibanian				Middle Pleistocene					Ionian	Rancholabrean	0.129
		Chibanian	Cudahyan/Sappan			Middle Pleistocene					Ionian	Irvingtonian	0.21
		Calabrian	Cudahyan/Sappan			Early Pleistocene						Irvingtonian	0.774
		Calabrian	Senecan/Rexroadian									Blancan	1.4
		Gelasian											1.8
Neogene	Pliocene	Piacenzian				Late Pliocene	Villanyian	Tertiary †					2.58
		Piacenzian				Late Pliocene	Ruscinian						3.1 *
		Zanclean				Early Pliocene							3.6
		Zanclean	Late Hemphillian/late Early Hemphillian/early Early Hemphillian			Early Pliocene						Hemphillian	4.7
	Miocene	Messinian				Late Miocene	Turolian						5.333
		Tortonian					Turolian						7.246
							Vallesian						8.7
			Late Clarendonian/Early Clarendonian				Vallesian					Clarendonian	9.4
		Serravallian	Late Clarendonian/Early Clarendonian			Middle Miocene	Astaracian					Clarendonian	11.63
		Serravallian	late Late Barstovian/early Late Barstovian/Early Barstovian									Barstovian	12.5
		Langhian											13.82
		Burdigalian				Early Miocene	Orleanian						15.98
			Late Hemingfordian/Early Hemingfordian									Hemingfordian	16.3
			late Late Arikareean/early Late Arikareean/late Early Arikareean/early Early Arikareean	Harrisonian								Arikareean	18.5
							Agenian						20
		Aquitanian					Agenian						20.44
Paleogene	Oligocene	Chattian				Late Oligocene							23.03
				Monroecreekian									23.1 *
				Geringian									24.7 *
		Rupelian		Geringian		Early Oligocene							27.82
												Whitneyan	29.5
												Orellan	31.8
	Eocene	Priabonian	Late Chadronian/Middle Chadronian/Early Chadronian			Late Eocene						Chadronian	33.9
		Priabonian				Late Eocene						Duchesnean	37
		Bartonian				Middle Eocene						Duchesnean	37.71
		Bartonian	Late Uintan/Early Uintan									Uintan	39.7
		Lutetian	Late Uintan/Early Uintan									Uintan	41.2
		Lutetian	Twinbuttean/Blacksforkian/Gardnerbuttian									Bridgerian	46.2
		Ypresian	Twinbuttean/Blacksforkian/Gardnerbuttian			Early Eocene						Bridgerian	47.8
			Lostcabinian/Lysitean/Graybullian/Sandcouleean									Wasatchian	50.5
					Cf3/Cf2/Cf1							Clarkforkian	54.9
	Paleocene	Thanetian			Cf3/Cf2/Cf1	Late Paleocene						Clarkforkian	56
		Thanetian			Ti6/Ti5/Ti4/Ti3/Ti2/Ti1	Late Paleocene						Tiffanian	56.2
		Selandian			Ti6/Ti5/Ti4/Ti3/Ti2/Ti1	Middle Paleocene						Tiffanian	59.2
		Selandian			To3/To2/To1	Middle Paleocene						Torrejonian	60.9
		Danian			To3/To2/To1	Early Paleocene						Torrejonian	61.6
		Danian			Pu3/Pu2/Pu1	Early Paleocene						Puercan	63.8
Cretaceous	Late Cretaceous	Maastrichtian											66
		Campanian											72.1
		Santonian											83.6
		Coniacian											86.3
		Turonian											89.8
		Cenomanian											93.9
	Early Cretaceous	Albian											100.5
		Aptian											113
		Barremian											121.4
		Hauterivian											125.77
		Valanginian											132.6
		Berriasian											139.8
Jurassic	Late Jurassic	Tithonian											145
		Kimmeridgian											149.2
		Oxfordian											154.8
	Middle Jurassic	Callovian											161.5
		Bathonian							165.3
		Bajocian							168.2
		Aalenian							170.9
	Early Jurassic	Toarcian							174.7
		Pliensbachian							184.2
		Sinemurian							192.9
		Hettangian							199.5
Triassic	Late Triassic	Rhaetian							201.4
		Norian							208.5
		Carnian							227
	Middle Triassic	Ladinian							237
	Middle Triassic	Anisian							242
	Early Triassic	Olenekian							247.2
	Early Triassic	Induan							251.2
Permian	Lopingian	Changhsingian							251.902
	Lopingian	Wuchiapingian							Longtanian †	254.14
	Guadalupian	Capitanian								259.51
		Wordian								264.28
		Roadian								266.9
	Cisuralian	Kungurian								273.01
		Artinskian								283.5
		Sakmarian								290.1
		Asselian								293.52
Carboniferous	Pennsylvanian	Gzhelian								298.9
		Kasimovian								303.7
		Moscovian								307
		Bashkirian								315.2
	Mississippian	Serpukhovian					323.2
		Visean					330.9
		Tournaisian					346.7
Devonian	Late Devonian	Famennian					358.9
	Late Devonian	Frasnian		372.2
	Middle Devonian	Givetian		382.7
	Middle Devonian	Eifelian		387.7
	Early Devonian	Emsian		393.3
		Pragian		407.6
		Lochkovian		410.8
Silurian	Pridoli			419.2
	Ludlow	Ludfordian		423
	Ludlow	Gorstian		425.6
	Wenlock	Homerian		427.4
	Wenlock	Sheinwoodian	430.5
	Llandovery	Telychian	433.4
		Aeronian	438.5
		Rhuddanian	440.8
Ordovician	Late Ordovician	Hirnantian	443.8
		Katian	445.2
		Sandbian	453
	Middle Ordovician	Darriwilian	458.4
	Middle Ordovician	Dapingian	467.3
	Early Ordovician	Floian	470
	Early Ordovician	Tremadocian	477.7
Cambrian	Furongian	Stage 10	485.4
		Jiangshanian	489.5
		Paibian	494
	Miaolingian	Guzhangian	Series 3 †	497
		Drumian		500.5
		Wuliuan		Stage 5 †	504.5
													509